The UW is a world leader in the emerging field of Affective Neuroscience, the multi-disciplinary approach to understanding the neurobiological bases of emotion. In addition, the UW excels in the imaging sciences and is preeminent in the use of nonhuman primates to study and model human disease. UW researchers have a long tradition of using Positron Emission Tomography (PET) to study nonhuman primates. However, the current human scanners only allow for the resolution of large brain regions (>5mm). In addition, to studies in rhesus monkeys, we have important projects in marmosets, a primate species that is much too small to image with the current scanners. Therefore, we are requesting funds for a high resolution animal PET scanner that will bring state-of-the-art scanning to our primate studies. These studies will investigate the function of neural circuits and require the ability to image small and discrete brain regions. At UW several major research programs have been established to focus efforts in brain and behavior research. These efforts uniquely integrate preclinical and clinical approaches to explore basic brain mechanisms. The HealthEmotions Research Institute (HERI) was recently established at UW to organize and extend these efforts. HERI's mission is to develop state-of-the-art scientific methods to support interdisciplinary efforts to explore brain function as it relates to human emotion, health, and disease. The Wisconsin Regional Primate Center and the Harlow Primate Laboratory are also located on the UW campus. A critical aspect of our work is the ability to perform mechanistic studies linking nonhuman primate studies to clinical research. Dedicated to understanding brain development as it relates to learning and behavior, the Waisman Center is another valuable resource. The Keck Foundation recognized the excellence of the Wisconsin programs in brain and emotion research by recently joining with the UW to establish the Keck Laboratory for Functional Brain Imaging and Behavior. This world class functional imaging laboratory, housed at the Waisman Center, contains clinical PET and a 3T MRI, and importantly facilities for studying nonhuman primates. The funds requested will purchase a high sensitivity, high resolution (2mm cubic) MicroPET scanner to support and extend ongoing animal PET imaging research programs while complementing human imaging studies. This dedicated animal research scanner will be jointly administered through HERI and Waisman Center and will be a core component of the Keck Lab. This scanner will also enhance research efforts in such wide-ranging areas as cardiology, oncology neurology, radiology and medical physics.